Timing device



C. BRADLEY Dec. 29, 1953 TIMING DEVICE 2 Sheets-ShedI 2 Filed Aug. 26, 1952 W w, O ma m W Patented Dec. 29, 1953 TIIVIIN G DEVICE Caton Bradley, Middletown,

The Sessions Clock Company,

Conn., assigner` to Forestville,

Conn., a corporation of Connecticut Application August 26, 1952, Serial N o. 306,475

Claims.

This invention relates to timing devices in general, and to variable timing devices in particular.

It is an object of the present invention to provide a timing device of a type which relies for its timing function on the predetermined running time of an electric motor such as an alternating current motor of the synchronous type, for in stance.

Another object of the present invention is to provide a timing device of this type in which each timing cycle is controlled by mechanism which is driven by the timer motor and automatically interrupts the circuit of this motor after a predetermined running period of the latter.

It is a further object of the present invention to provide a timing device of this type which is suited especially, though by no means exclusively, for timing the performance of a great variety of diierent apparatus which require for their performance or for the control thereover an electric circuit in which the instant timer motor and a switch may readily be interposed, so that the aforementioned motor-driven mechanism may at the end of each timing cycle actuate this switch and thereby not only interrupt the circuit of the timer motor but the operating or control circuit of the apparatus as well.

Another object of the present invention is to provide a timing device of this type which readily lends itself to timing the performance of other kinds of apparatus of which the prime mover may be the instant timer motor, in which case the mo tor shaft becomes the main drive shaft of the apparatus and a predetermined time cycle of operation of the apparatus will be concluded whenthe aforementioned motor-driven mechanism interrupts the circuit of the timer motor.

A further object of the present invention is to provide a timing device of this type which 1s presettable for varying its timing cycle by relatively small time increments so that the same may readily be adapted to apparatus requiring accordingly narrow time-cycle variation.

It is another object of the present invention to provide a timing Adevice of this type which is presettable for varying its timing cycle not only by relatively small increments but within exceptionally wide overall time limits as Well, so that the instant device is suitable for different apparatus having widely differing time-cycle requirements.

Another object of the present invention is to provide a timing device of this type of which the aforementioned switch is normally closed, and the motor-driven mechanism includes a movable member which at the conclusion of each timing cycle is automatically returned into a home position in which to open this switch, and which for each timing cycle is set or moved away from home position so that the setting of this member for the next timing cycle will immediately start not only the latter but also the operation of any apparatus with which the instant device is associated in any of the aforementioned ways.

It is a further object of the present invention to provide a timing device of this type of which the aforementioned movable member is settable at variable distances from its home position for according variation of the ensuing timing cycles thereof, and this member is operatively connected with the timer motor so that the same will be returned by the latter into its home position at the end of each timing cycle, or may quickly be returned manually into its home position to interrupt any timing cycle at any time if this should be necessary or desired.

It is another object of the present invention to provide a timing device of this type which is exceedingly simple, rugged and condensed in its construction, yet highly reliable and accurate in its performance over a long period of use, and which readily lends itself to efficient mass production at low cost.

Other objects and advantages will appear to those skilled in the art from the following, considered in conjunction with the accompanying drawings.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

Fig. l is a front view of a timing device embodying the present invention;

Figs. 2 and 3 are side views of the instant timing device as viewed in the directions of the arrows 2 and 3, respectively, in Fig. l;

Fig. 4 is a rear view of the timing device;

Fig. 5 is an enlarged section taken substantially on the line 5-5 of Fig. 1;

Fig. 6 is a fragmentary section similar to a part of Fig. 5, but showing certain operating parts at a different operating condition of the timing device; and

Fig. 7 is an enlarged side view, partly in section, of a part of a timing device in which the present invention is embodied in a modified manner.

Referring to the drawings, and more particularly to Figs. 1 to 4 thereof, the reference numeral l0 designates a timing device of which the various operating parts are carried by a panel l2 and a base I4 which are suitably joined at I6, as by spot at and is hereinafter referred to as the timer., shaft. The timer shaft 3e extends to the rear `of the panel l2 through an aperture 32 therein (Fig.

l) and is provided with a screw-thread 3d. Therl screw-thread 311 is, in the present instance, formed:

directly on the timer shaft 3Q.

Suitably mounted on the front ofthepanel i2V is a snap switch i, having a depressible element 38 for actuating the switch (see also Fgs..v5 anda...

6). The switch 35 is provided with terminal tabs 4G and d2 (Figs. l, 4 and 5) for the connection of the companion contacts, respectively, of the switch with leads to be described l l Suitably mounted at @.3 on the base ill isa bracket d4 having an arm i5 spaced from the base it. J ournalled in the base lli and the arm t of the bracket it is a control shaft d6 on which is mounted the hub i8 of a ratchet disc 5i! the teeth 52 of which may conveniently: be inthe form of gear teeth. Cooperating with the ratchet disc 5tis an indexing pawl Eidwhich in this instance is formed by an apprcpriatelybent Vend of a leaftype spring 55 which. is anchored with its other end on the rear of the panel I2 as at 58 (Figs. e and 5).Y As will be described more fully herein-v after,.the pawl end 54 of the leaf spring 56 is adapted to index the ratchet ,disc Ekin clockwise, direction as. viewed. in Fig.v 5. Riveted. or other n wiselsecured at tato the bracket Mis one end of another leaf-type springZwhichV` is formed as shown in F195 and held! iny .yielding engagement with thev vteeth of the ratchet disc 50 toserve as a holding pawl which prevents rotation off the'.

ratchet disc opposite .to itsindexing direction.

Welded or otherwise securedto ythe rear. of the panel l2 is an anchor plate Eli having an eye for-l mation 66 in which is pivotedan intermediate.

bent portion 68 of a, feed rod or element '10. The

feed rod 'l0 is in this instance made of spring wire..

and its pivot mounting is so arranged that ythe screw-thread 34 on the timer shaft 30. Further,-

r Y A rod is normally yieldingly urged against` vthemore, the lower end of the feedrod 'l0 is bent.

so as to extendtransversely ofthe timer shaft 30A and be normally in registry or mesh with V`the screw-thread 3d thereon (Figs. 2.and v5). V

The screw-thread Sten the timer shaft 30,is,

during normal running of the latter, adapted to.

feed the rod 'i6 `from the startingposition shown in Fig. 2 forwardly in the direction of the arrow 12 for some distance,whereupon the rod is permitted to disengage from thescrewfthread 3ft and.:v

return to its starting position for a repeat forward feed by the screw-thread 34. To this endV there is suitablyfmounted at 14. in back of theA panel l2 a bracket 'i6 (Figs. 2 and 4 1) of which4v an upstanding leg serves asa rodguide i3.l One face Bil of the rod-guidelS is flat andis inclosez.V

proximity to an axial-length of the screw-thread 34 (Figs. 4 and 5) in order positively to retainthe rod 1B in feeding relation with this axial thread length. Accordingly, the rod in its starting position (Fig. 2) will, on rotation of the timer shaft 30, be fed forwardly by the screw-thread .34 at least until the rod clears the adjacentface 3a of.

the guide 18 (Fig. 6) In the present instance, the width of the rod-guide l2 is such as to span three consecutive turns of the screw-thread 3e, and the guide iii is located in front of, but closely adjacent to, the starting position of the rod 'HJ (Figs. 2 and 5) to assure the unfailing feed of the rod through the axial extent of these three turns of the screwthread `after eachvreturn of the rod .to its starting position. Y

For its return into starting position, the rod 10 is at the end of each feed stroke thereof biased rearwardly over the other or lead-back face 82 of the guide 18. To this end, a bent end 8d of the rod 1i), bears againsta vpanel wall 86 in the manner shown inFigs; 2 and 3 so `as yieldingly to urge the rodi'i into `its-starting position in which the same bears against aank 88 of one of the turns of the screw-thread 34, in this instance the one nearestthe panel l2. It will also be observed from Figs, 2 and 3 that the restrained rod lil will further be resiliently tensioned whilepassillg through eahfeed Strokeso that the rod ,will assuredlyjc jump or snap back into its startingpositionwhen clearing the face 3Br ofthe guide kI8A ati-the y en d ofA each feed stroke. ,The Vlead'bnackf acei324 ofgtheg IOfcgl'e 73 may be; Cam. 01V Wedge-...Shaped 1in; 2in manner like or similarto'thatshowninvFigs. 5 and 6, so that this face of the guide 18 will; m5., the yieldingly-urged rod l2 back toits starting position without offering vanyappreciableresist-- ance to the same. While the yrod l0 is normallyl., yieldingly urged into meshing `en*gagement with., the screw-thread 3d as explainedthe increasing',l tension in the rod during each feedstroke there f. of is sufficient to counteractits tendency .tor reginain in engagement with the screw-threadand, to withdraw the rod from the thread .and .retract it over the guide l2. Thus, the rod 'l0 will, while Y the motor 2Q is running, have periodic feed strokes and quick return strokes, andthe pathof the rod is circuitous around the guide 18,: as will be read-.i ily understood.

To facilitate the withdrawal of the rod l'IG from the screw-thread 3d at the end of each .feed .i stroke, the ank 88 ofthe screw-thread.BAwhi-ch. faces away` from the panel l2 is preferably beveled as shown, so that thisthreadflank,forms,V in fact a continuation of the lead-.backrface 812 of the rod-guide 'i8 (Fig.g6 andwill :offenas little resistanceto the retraction of the Arod as does the guide 18.

The feed rod l0 is adaptedto actuate vrthe `ir 1`..,y dexing pawl54 during each feedstroke thereohz To this end,the leaf-spring 55 is normally ,urged-b. into the idle or home position shown in Figa-,2.,- and 5 in which the same extendsinto `a lno tch i 90 on the front sideof the rod-guide J8. With y this arrangement, the feed rod 'IU will duringthe latter'part of each .feed stroke thereof d isplacef, the leaf-spring 5.6v from the-position shownin j Fig. 5 into that shown in Fig. `6, causing-thereby@ the pawl 54 t0 index the ratchet disc 50, in this1 instance the distance ofone tooth 52.-.Fig., 6` shows `the rod vI0 at the end ofV al feed-stroke thereof, and in a position where it has rjust started its return stroke into starting position. As soon as the rod 'ill isatvthe endokf-each-feed,` stroke released by the guide `face 30 for its re.v traction or reverse ystrokeinto starting posi-tion, z the leaf-spring 56 and Ithe .pawl end 5d thereof, will yieldingly be returned into the idle position shown in, Fig. "5, the holdingypawl 52j meanwhile-.- preventing reverse rotation of the ratchet discl 50, as will be readily understood.;

The ratchet disc-,5B carriesfaswitch-actuator;

which in this instance is in the form o1' a roller 92 that is adapted to depress the switch element 38 and actuate the switch 36 when the ratchet disc arrives in a certain operative position. Thus, the ratchet disc 50 is in its illustrated position in Fig. 6 one indexing step away from this operative position, although the switch element 38 is already slightly depressed by the roller 92 but not sufficiently to actuate the switch 36. The actuation of the switch 36 will in any event terminate a, timing cycle of the instant device regardless of the manner in which the latter is used for timing purposes.

The control shaft 46 preferably carries a convenient knob (not shown) by means of which to turn or preset the ratchet disc 50 for a selective timing cycle of the device. In this connection, it will be observed that the holding pawl 62 will prevent rotation of the ratchet disc 50 opposite to its indexing direction, but the pawls 62 and 54 are so arranged that they will never interfere with manual rotation of the ratchet disc in indexing direction. Thus, depending on the manual setting of the ratchet disc U, i. e., the angular spacing of the roller 92 on the preset ratchet disc 50 from the switch element 38, the following timing -cycle of the device will have an according duration. It is now obvious that the duration of any timing cycle of the device may be selected at will and within very considerable overall time limits.

In the present instance, the switch 36 is in series connection with the eld coil of the motor 24 and is, accordingly, in the motor circuit. Thus, the motor lead 26 (Fig. 1) is connected to the terminal tab 42 of the switch 36 as shown in Fig. 4, and the other terminal tab 40 is connected to a lead 93 which forms part of the circuit of the motor 24. In this instance also, the snap switch 36 is normally closed, and is opened on depression of the switch element 38. Accordingly, a timing cycle of the device will have been concluded, and the motor 24 will also stop, when the ratchet disc 50 arrives in the hereinbefore mentioned operative position, rendering thereby the entire timing device idle. Furthermore, the described presetting of the ratchet disc 5U away from its operative position will also effect an immediate start of the motor 24 and, accordingly, immediate initiation of the next timing cycle of the device. Also, any started timing cycle of the device may, if necessary or desired, be interrupted immediately at any time by simply turning the ratchet disc 5U manually into its operative position.

The circuit of the motor 24 and timer switch 36 may readily be extended so as to be the operating or control circuit of an apparatus the operation of which is to be timed by the instant device. In that case, the entire operation of the apparatus may be under the final control of the instant device to the extent that mere presetting of the ratchet disc 50 will immediately initiate a. timed operating cycle of the apparatus, and manual rotation of the ratchet disc at any time into its operative position will interrupt any started operating cycle of the apparatus.

If power factors permit, the timer shaft of the instant device may also be used directly as the main drive shaft of other apparatus the operation of which is to be timed. Any secondary drive shaft orshafts of the apparatus could be driven at any desired speed from the timer shaft 30 through intermediation of suitable reduction or speed-up gearing, as the case maybe. n

While by no means limited to timing cycles of relatively long duration, the instant device is especially suited for relatively long timing cycles such as are used for driers, for instance. Considering, as an example only, that the prime mover 24 is a low-speed synchronous motor having additionally a reduction gearing, then each feed stroke of the rod l0 may take in the neighborhood of two minutes, for instance. If the ratchet disc 50 is sufficiently large to accommodate a. very considerable number of teeth 52 of the right dimensions, it will be readily understood that the instant device would then be capable of timing cycles that may vary from a few minutes to over an hour or even hours.

An entirely different range or ranges of the possible timing cycles of the instant device may be added by making the rod-guide of varying width and providing for adjustable mounting of the the same so that portions thereof of differnt widths may be brought into operative relation with the threaded timer shaft 30. Fig. 'I shows an example of such an arrangement. Thus, a rod-guide 18 is at one side tapered so as to have minimum and maximum widths to span, in this instance, two and three turns, respectively, of the screw-thread 34 on the timer shaft 3U. The rodguide 'I8' has a rear shank |00 which is longitudinally slotted at |02 for the reception of mounting screws |04 in a bracket |06 on the panel 2. In the instance shown in Fig. 7, the rodguide 'I8' is so adjusted that its minimum width is in operative relation with the threaded timer shaft 30, i. e. two turns of the screw-thread 34 are spanned by the rod-guide. However, the rodguide 'I8' may be adjusted so that its maximum width is in operative relation with the threaded timer shaft 30, in which case three consecutive turns of the screw-thread 34 would be spanned by the rod-guide and each feed stroke of the rod l0 would accordingly require one and one-half times as much time as in the preceding example.

The taper of the rod-guide '|8 is necessarily such that the feed stroke of the rod 10' is under the full control of the particular width of the rodguide adjacent the threaded timer shaft 30 and is not interfered with by the rod-guide regardless of its adjustment. Further, since the leaf-spring 56', which provides the indexing pawl for the ratchet disc, is in this instance permitted normally to bear against the rod guide as shown, and in order that the rod l0 may on each feed stroke thereof displace the leaf-spring 56 sufficiently to accomplish and indexing step of the ratchet disc, the rod 'I0' is provided with a collar |08 which will engage and displace the leaf-spring 56' in good time before the rod reaches the end of its feed stroke.

The invention may be carried out in other specifc ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming Within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

1. In a timing device, the combination of a 'power-driven screw-threaded spindle; a feed rod laterally movable transversely and longitudinally of said spindle and normally yieldingly urged against the screw thread into feeding relation therewith and also in a starting position thereon longitudinally of the spindle; a guide having oppsiteisurfaces. of. which'one surface extends-from adjacentssaid starting positionl in Iclose proxin-iityto 'and` along ani axial 'length tofthe screw thread@ inthe feeding-directionof-.the rod -to reta-in the 1' latterT in 1 feedingrelation-with Ythe screw threadvv` throughout `said length thereof; -and the =other i surface is -shaped to guide the Vyielliingly-urged-K- rod loa'ck` into' said starting pcsitionon clearing saidy one guide-surface atthe -^end of each feed stroke; Y and means f including' au timer element for actua-ting the latter on each feed stroke; of said i Todina.

vf2. Thefcomb-inationin a;timingjdevi ce as set forthin-claim l,r in which said guide is `'sulost antially wedge-shaped sov as graduallyto cam-the yieldingly-urgedrod back into said starting position;

3. lThe"combination in a timing device as set forth in claim`1, in which said rod is resilient and is pivoted remote from said spindle for rotation about-van axis transverse -tothe spindle axis sov that saidprod is normally resiliently urged vagainstv the screw thread. v-

4. -The combination in a timing device asi-set forth in claim l, in which said rod is resilient; andv there is further provided a support onr whichsaid rod is, vnear an end thereof remote from said spindle,`pivoted'for rotation about anaxis transverse v to the spindle axis so that said rod is normally resiliently urgedagainst :the screwthread, and said; rod endbears Vagainst said support so that .said Vrod Vis resiliently tensioned during each feed strokethereof for its yielding return into said starting position.

5. The combination in a timing` device as set forth in claim 1, in which the flank of the screw' also into ay starting position thereon longitude nally of said spindle; a guide havingopposite 'sur-V, facesof which one surface extends from adajcent.

said starting position in closeproximity to and along anl axial length of the scre'vvthread inthe feeding direction of said rod to retain thelatter in feeding relation with the screw-thread throughg out saidlength thereof, and the other 'surface'- is shaped to guide the yieldingly-urged rod back into said` starting position on clearing said one guide surface'at the end of each feed stroke; an operi-v able control member; a ratchet disc having means for operating said control member in an operative position of said disc; and a pawl actuated by said rod on successive strokes thereof .-in one directionv to index .saiddisc step-bystep ,towardtand vinto..

said. operative position. Y

7.-A timing device as set forth in .claim` 6, in whichv saidpawl 'is actuatedV byv saidvv rod on suc-f cessve feedv strokes thereof; c

8. A timing device as set forth irnclaim.;:GrinV which said ratchet disc is manually turnable from said; operative positionintoidifferent positions remote therefrom for selective timing ofthe device.'-

9. A'timing device `asset forth in claim', fur

ther 'comprising a holding pawl to 'prevent rota- -f I tion-I of said. disc in a directionopposite to its indexing direction and said disc is manually turnaloleiv in said,` indexing.;-.direction .ffromf-saidoperative position into. different-,positions remotes;

therefrom `for selectiveitirrling vof 1 the deviceV which said controlrnember-:is an electric iswitch.; having a depressiblc-i'element .for actuatingthea* switch,iand saidratchet disc hasta cam projecs; tion-infor depressing. said -switch-ielement-whena said disc turns intoixsaid opera-tive: position thereof. Y',

11. AY timingfdevicefas-set forthin claimsbs-inl Y which-tsaid guide- 'extends longitudinally; trans-uff. versetto. the spindle axisiandhas llongitudinally s spaced different widths to span-correspondingly:Vv

different faxiallengths of the yscrewthreadgan'd said ...guide is longitudinally:adjustable tobringzi.

anytzone of itsdiiferent widths-intoY operative ree, f

lationwith the screw thread: y

12. A* timingv device; .comprising i an electrics; motor;-.a screw-#threaded spindle .driven -bysaid motoryfa feed rod laterally;movableltransverselyfa and ilongitudinally of said spindle and vnormal-ly L,

yieldingly.; urged against the-screw thread iintof:` feedingfrelatio'n therewithand also .into a start ing position thereon'longitudinally Vof saidfspin-,

' dlegv-a guide having: opposite surfacesuof which.;

one .surface .extends from adjacent said-starting; a position in closeproximityto and'along an' axialile length of the screw thread in the feeding direcerf tionziof saidrod to retain .thev latter in feeding-. relation: with the `screw thread `fthroughout'l saldi..

length thereof, and the other surface "-isfshapede to guide the yieldinglyfurged rod loaclcintoisaid starting position on clearingsaidfone guide sur-e` faceV atthe end of each feed stroke; an electric?l switch-having. a. depressible element-for actuaire.

ing the switch; a ratchet dischaving axcam pro-fjectionl for depressing said' switch element .whene-y said discturns into ank operatiVeposition; -andiaa pawl actuated by' said-rod on successive-strokes thereof inone direction to index-said disc step@ by-step toward and intoffsaid operative positions?` 13. A timing device,y comprising" an electric: motor; a screw-'threaded spindle Vdrivenlzby said@l motor; la feed rod laterally vmovable transversely:

andslongitudnally of 'said spindle and normally@ yieldingly urged.

.against .the `screw. thread intoif feeding `relation .therewith andfalso ,into a-iistarte.V f ing positionzthereon longitudinally `of said. spin-5 dle'pa' guide having opposite surfaces ofiwhichz one surfacefextends from adjacent saidstartings-j position in'close'proximity to and along-an axia lengthi of the screw` threadzin vthe feedingfdirec tionrof said=rod to'retain the latterfinv feeding l relation v with:- the screwf thread throughout: saidaf length thereof, and the other surfacefisshaped to guide the yieldingly-.urged rod Vhack .into jsaid starting: position on clearingisaidtonezguide .surr. facefatl the end ofeach feed stroke; a normally. closedelectric switch'iin' the circuit4 of said; motor,r i

saidswitch having adepressible elementffor" opening theswitch; a ratchet disc havinga'cam'v projection for depressingsaid switch Alelementl whenflsaid disc turns intof an operative yposition andafpawl actuated by 'said rod ron successive-"- strokes thereof in one directiontoindexisaiddiscE step-by-stepv toward andY into' said: operative poe? sition.

i4. Aftimingdevice'asset forth in c1aim 13,iin y which`said-motor1is va synchronous alternating currentv motor.-

15.V Atiminge-deviceas set forth'in claim'lyinf Whichsaid ratchet disc yis manually turnable'fromg; said 1 operative position 'into different *positions* remote-therefrom for closure of saidY-switch'and-A selective timing-of `the device.

16. A timing device as set forth in claim 13, in which said ratchet disc is manually turnable from said operative position into different positions remote therefrom for closure of said switch and selective timing of the device, and is also manually turnable from any position into said operative position to open said switch at will.

17. A timing device as set forth in claim 13. further comprising a holding pawl to prevent rotation of said disc in a direction opposite to its indexing direction, and said ratchet disc is manually turnable in said indexing direction from said operative position into different positions remote therefrom for closure of said switch and selective timing of the device, and is also manually turnable in said indexing direction from any position into said operative position to open said switch at will.

18. A timing device, comprising a power-driven screw-threaded spindle; a feed rod laterally movable transversely and longitudinally cf said spindle and normally yielding'ly urged against the screw thread into feeding relation therewith and also into a starting position thereon longitudinally of said spindle; a guide having opposite surfaces of which one surface extends from adjacent said starting position in close proximity to and along an axial length of the screw thread in the feeding direction of said rod to retain the latter in feeding relation with the screw thread throughout said length thereof, and the other surface is shaped to guide the yieldingly-urged rod back into said starting position on clearing said one guide surface at the end of each feed stroke; an operable control member; a rotary gear disc having a multiplicity of gear teeth and being provided with means for operating said control member in an operative position of said disc; and a leaf-type spring anchored at one end and having its other end formed to serve as an indexing pawl for said gear disc, said spring being engaged and displaced by said rod on successive strokes thereof in one direction to cause said pawl end to index said gear disc step-by-step toward and into said operative position.

19. A timing device as set forth in claim 18, in which said spring is engaged and displaced by said rod on successive feed strokes thereof.

20. A timing device as set forth in claim 18, further comprising another leaf-type spring anchored at one end and having its other end formed to serve as a holding pawl for said gear disc to prevent rotation of 'the latter opposite to the indexing direction therecf.

CATON BRADLEY.

References Cited in the le of this patent UNITED STATES PATENTS 

